Inking systems or dampening systems, for use in printing presses, are used for conveying the printing ink that is required for the printing process or for conveying the required dampening agent from appropriate supply devices to the printing zone. Rollers or cylinders are provided in the inking system or in the dampening system for forming the ink film or the moisture film required for this. The terms roller and cylinder will be understood to have the same meaning in connection with an understanding the present invention. The rollers come to rest against each other at roller strips, so that the ink film or the moisture film can be transferred from one roller to another roller in the area of these roller strips. Rollers which are displaceably seated in a machine frame, are provided in connection with such inking systems or dampening systems. By displacement of these displaceably seated rollers, in relation to the other rollers, it is possible to change the contact pressure in the roller strips.
A roller seating which is adjustable only in one direction is known from DE 15 61 014 C1, and is intended for use, in particular, for distributing and for application rollers of inking systems in printing presses. Adjusting mechanisms for displacing the roller transversely in respect to its axis are provided. The adjusting mechanisms are attached between a bearing journal, which is connected with the frame wall, and a housing, which receives a roller end and which is preferably configured in a cup shape. The bearing journal and the housing are connected with each other by spring elements which act counter to the adjusting means. In this case, the spring elements are preferably configured as radially extending rubber bumpers and the adjusting mechanisms acting on the bearing journals are provided either as a radially arranged adjustment screw or as two adjustment screws that are arranged at 45° in relation to each other. In accordance with a further embodiment of this prior device, moving the roller in and out of contact, and therefore accomplishing the adjustment of the roller seating, can also take place by the use of two pressure chambers, which are arranged diametrically in the interior of the housing and which can be charged with air or a fluid. The counter-acting pressure chambers are selectively charged with a pressure, depending on the desired direction of their action.
Devices for setting a contact pressure of a displaceably seated roller are known from WO 02/074542 A2 and DE 101 13 313 A1, from which it claims priority. A diaphragm encircling a holder forms four pressure chambers in a gap between the holder and a sleeve surrounding it. The gap between the holder and the surrounding sleeve is open and unprotected in this prior device.
A cylinder-piston unit for use in displacing a roller transversely, with respect to its longitudinal axis, is known from DE 39 10 827 A1. An annular gap exists between the piston, which is embodied as a lifting piston and which is arranged transversely with respect to a longitudinal axis of the roller, and the inner cylinder wall. A stripper ring bridging the annular gap and two units, which are spaced apart from each other in the axial direction of the lifting piston and which seal the annular gap, are each provided with an elastic sealing ring. The stripper ring and the support rings of the sealing rings can be radially displaced in accordance with a transverse displacement of the piston in the cylinder. Thus, the stripper ring and the sealing rings follow the transverse displacement of the piston substantially without changing their shapes.